In this continuing study of connective tissues the joint cartilage in hemophilic arthropathy has been examined using the scanning electron microscope equipped with an energy dispersive x-ray analyzer. Now the effort will be directed toward the chemical and morphologic changes in elastin during the development of "senile elastosis". BIBLIOGRAPHIC REFERENCE: Hough, A.J., Banfield, W.G., and Sokoloff, L: Ultrastructural and microanalytical studies of cartilage in hemophilic arthropathy. Arch. Pathol. 100: 91-96, 1976.